关于膜宇宙模型的宇宙学演化(英文)

COSMOLOGICAL EVOLUTION FOR A BRANE UNIVERSE MODEL

最近Randall和Sundrum提出了一个非紧致的额外维模型,Binetuy等人得到了修正的弗里德曼方程,在这个方程中膜宇宙的能量密度以平方的形式出现,而不是象在标准那样成线性关系,他们在膜中引入了一个正好补偿在体中的宇宙学常数的张力常数,这样方程中的主导平方项被抵消,剩下膜中能量密度的一个线性项和一个附加的平方项,我们研究了这种新模型的几种宇宙学效应,并且得到了尺度因子一个通解。

An noncompact extra dimension model was recently proposed by Randall and Sundrum. Binetruy et al. obtained the modified Friedmann equation, in which the energy density in the brane appears quadratically in contrast with the linear behavior of the standard equation. Then they put a cosmological constant in the bulk and introduce n the brane a constant tension that exactly compensates the bulk cosmological constant so that the quadratic leading order be cancelled, leaving the linear order and a additional term that is quadratic of the energy density in the brane. We investigate kinds of cosmological effects of the new models and get a general solution of the scale factor.